Spray Foam Insulation – Open Cell Foam Vs Closed Cell Foam
If you are interested in getting Spray Foam Insulation in your home or other building you must read this. Which Spray Foam product should you put in your home or commercial building structure. You must decide whether you will use .05 lb./cu. ft., open cell foam, or 2.0 lb./cu. ft. closed cell foam. This makes a big difference in product performance, application processes and consumer cost.
There are two big factors to understand and consider when comparing open cell and closed cell spray foam. The first is the physical makeup of the foam. It is either open-cell foam, where the small cells of the foam are not completely closed. They are open and air fills all of the tiny air pockets in the material. This makes the foam structurally weaker and much less water resistant than closed-cell foam.
Closed-cell foam is also made up of small foam cells BUT its tiny foam cells are closed and packed together. They are filled with a gas, not air, which makes the foam rise, expand and become a much greater, more thick and completely waterproof insulator.
Weighing one cured cubic foot of foam material gives us a measurement of its density. Open cell foams usually weigh in at 0.4 to 0.5 lb./cu. ft. Closed cell foam, used for insulating applications, have a density of 1.7 lb./cu. ft. to 2.0 lb./cu. ft. Roofing applications typically use an already greater density foam to sustain greater loads. The higher the density the foam the stronger it will be. Many polyurethane foams can turned into decorative moldings and painted/stained to look like wood. There are “super thick” foams with densities of 30 lb./cu. ft. to 40 lb./cu. ft.
There are numerous advantages for using closed-cell foam as opposed to open-cell foam including its structural integrity, higher R-value, and its ability to completely seal air leaks and prevent water infiltration. The disadvantage of the closed-cell foam is the expense, because it requires more material as it contains no air. The decision of which foam to use will also be based on some application specific requirements such as load capabilities, vapor/water infiltration resistance, space limitations, etc. Open-cell Spray Foam typically has an R-value average of 3.5 per inch water is used as the blowing agent. Closed-cell Spray Foams Insulation typically has an R-value of around 7.0 per inch and uses high R-value blowing agents.
Both types of spray foam insulation are shared in many commercial and residential applications and are usually interchangeable. The information above hopefully has given you a better understanding about the differences between the two types of spray foam insulation. There are some applications in which you simply cannot use open cell foams. Be sure to contact a specialized spray foam insulation company before deciding which application will be the most effective.